Port 443 — HTTPS
HTTPS normally uses 443. HTTP/1.1 and HTTP/2 commonly use TCP/TLS; HTTP/3 uses QUIC over UDP, so TCP alone does not cover every deployment.
Registry assignments, software defaults and local listeners are different things. A port number alone does not identify or secure a service.
Configuration and troubleshooting
Check bind addresses, certificate hostnames and certificate chains. If HTTP/3 is enabled, also verify the UDP listener, proxy and firewall path.
Important limitations
A reachable port does not prove certificate trust. Do not permanently bypass certificate checks; failure of HTTP/3 need not imply failure of HTTPS over TCP.
Read-only checks: run on the server host
Choose the commands for your OS. Check TCP and UDP separately. No result is not a lasting availability guarantee; inspect host and container separately.
Linux
sudo ss -ltnp 'sport = :443'
sudo ss -lunp 'sport = :443'macOS
sudo lsof -nP -iTCP:443 -sTCP:LISTEN
sudo lsof -nP -iUDP:443Windows PowerShell
Get-NetTCPConnection -LocalPort 443 -State Listen
Get-NetUDPEndpoint -LocalPort 443Sources and review
Sources checked on:
This review covers the explanations and sources on this page, not your device or every community software entry below.
Related troubleshooting guides
Software Using This Port (9 software)
Community software entries: links are references, not individual verification.
Usage Suggestions
- Before using port 443, please confirm it is not occupied by other services
- If you encounter port conflicts, consider using other ports or stopping the occupying service
Quick Info
- Port
- 443
- Protocol
- TCP/UDP
- Categories
- Web & HTTP Services
- Usage Status
- 9 software in use
Related Ports
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